铸锻合金热处理工艺(英语课件).pdf

《铸锻合金热处理工艺(英语课件).pdf》由会员上传分享，免费在线阅读，更多相关内容在教育资源-天天文库。

1、6/23/2014铸锻合金热处理工艺及其一般问题HeatTreatmentProcessandCommonProblemsZhichao(Charlie)LiDANTESolutions,Inc.Date:May,2014Contents
Basicphasediagrams.•Iron-Carbonequilibriumphasediagram.•TTT/CCTdiagrams.
Classificationofheattreatmentprocesses.
Steelhardenabilityandeffe

2、ctofalloycontent.
Understandinghardenabilitycharacterization.
Typicalhardeningprocesses.Slide#2Iron-CarbonEquilibriumPhaseDiagramSlide#316/23/2014Iron-CarbonEquilibriumPhaseDiagram(cont’d)Slide#4TTT/CCTDiagrams
TherelationshipbetweenTTTdiagramandCCTdiagram.S

3、lide#5BasicPhaseStructuresMartensite-BCTAustenite-FCCFerrite-BCCFe3C(cementite)-orthorhombicSlide#626/23/2014HeatTreatmentProcessesandTTTDiagram
Diffusivephasetransformations•AF,AP,AB.
Diffusivelessphasetransformation•AM.
Heattreatmentstypes•Hardening•So

4、ftening•ConditioningSlide#7ClassificationofHeatTreatmentTypesSlide#8CommonHeatTreatmentProcesses
Annealing.•30-50°Chigherthanuppercriticaltemperature,andslowcool(infurnace).•Improveductilityandreducebrittleness.
Normalizing.•Similartemperatureasannealing,wit

5、aircool.•Finergrainsize.
Carburizing.•Increasesurfacecarboncontenthighhardnessandstrength.
Quenchhardening.•Martensitetransformation.
Tempering.•Convertbrittleas-quenchedmartensitetomoreductiletemperedmartensite.
Precipitationhardening.Slide#936/23/2014Typi

6、calPhaseMorphologyPearliteUpperBainiteLowerMartensiteBainiteSlide#10WhatisHardenability?
“Hardenability”istheabilityofFe-Calloytobehardenedbytheformingmartensiteasaresultofagivenheattreatment.Foreverydifferentsteelalloythereisaspecificrelationshipbetweenthem

7、echanicalpropertiesandthecoolingrate.•Jominytest.•TTTdiagram.•Dilatometrytest.•GrossmannHfactor：Idealdiameter(DI).Slide#11JominyTest
Generally,thefastersteelcools,theharderitwillbe.
TheJominybarmeasuresthehardenabilityofasteel.Slide#1246/23/2014JominyTest(co

8、nt’d)JominyCurvesofDifferentSteelGradesJominyCurveVariationofOneSteelGradeSlide#13EffectofAddingElementsonHardenability
Alloyelements(Cr,Ni,Mo,SiandMo)maycausesignificantchangesinthepositionsand